Detachable connecting means for cooling agents and current



Jan. 22, 1963 H. KOESLING ETAL 3 DETACHABLE CONNECTING MEANS FOR COOLING AGENTS AND CURRENT Filed June 30, 1959 2 Sheets-Sheet 1 INVENTOR Hein z Koes/m Y Oho 50 1 11 B M el AGE Jan. 22, 1963 H. KOESLING ET AL 3,075,163

DETACHABLE CONNECTING MEANS FOR cooLINGAGENTs AND CURRENT Filed June 30, 1959 2 Sheets-Sheet 2 INVENTQRS Hein 2 goes/m BY CH0 8 m 5M4 AGE hired rates The present invention relates to detachable connecting means for cooling agents and current for the inductor of an inductive heating device in which the ends of the inductor are provided with contact members for the supply of current and water, which members engage the corresponding contact blocks with a high contact pressure. Such connections are known per se, particularly for the transmi sion of the required heavy currents at high frequencies, various constructions are known. Since in the present electric circuits carry exceedingly heavy currents and the corresponding voltages are in general rather low it is of importance for such an electric connection to have as low as possible a contact resistance. It has therefore been attempted to construct the contacts so as to exert a high contact pressure. In designing junction contacts of this type, displacement of current wiich, as is known, occurs at high frequencies has been taken into account.

However, such a junction contact has a dual purpose. Not only should the electric current, possibly of comparatively high frequ ncy, be transmitted while minimizing the losses, but provision should also be made for the supply and exhaust of the cooling agent constantly required in the inductor. In this case water was generally used as a cooling agent. In addition, it is important that the junction contact can be detached and closed with a minimum number of manipulations, since in practice the inductors, necessary for heating the workpieces, require frequent replacement. In view of easy and fast operation, the junction contact was therefore generally constructed so that, whilst establishing the electric contact, also the connection for the cooling agent was established. For this purpose, the pressure of a screw or similar means, which brings about the required surface pressure of the electric contact, has at the same time been caused to act on the disc used for sealing the cooling agent connection.

it is obvious, however, that those known constructions do not always satisfy the stringent requirements imposed on them. The surface pressure of the electric contact should be as high as possible, while taking into account the mechanical strength of the material. In most cases, however, this pressure is prohibitively high for the sealing disc of the cooling agent connection, the disc being liable to heavy stress and strain so that it cannot satisfactorily perform its task for long.

This drawback is avoided by the invention. When using detachable connecting means for cooling agents and current according to the invention, the surface pressure required for the satisfactory passage of current is obtained with the aid of screws or similar pressure means acting on the contact members and the tight water connection is established by pressure means acting on the correspond ing sealing surfaces and being independent of said screws; which pressure means are so designed that practically no special attendance is required for establishing or detaching the connection and after inserting the inductor into the contact blocks, they immediately function automatically.

Preferably, the contact member and the contact block have the form of a cylinder which may be, hollow, and of a prism respectively and both are pressed together by the ice hdld tea 9 Patented Earn. 22, 196

contact pressure member at right angles to their longitudinal direction.

The supply or exhaust of cooling water occurs advantageously at the end of the contact member remote from the inductor. For this purpose, provision is made of a nipple with a stop comprising a. flexible sealing ring,

zhich, under the influence of the pressure of the cooling water, is pressed against the contact member, the nipple and the wall of the bore of the contact block. In a suitable form of the invention a cylindrical guide ring extending to the contact member and surrounding the nipple with clearance, is provided at the end of the bore in the contact block facing the cooling Water connection. This ring has such a size that, when likewise inserted on providing the contact member, it occupies the desired place at the end of this inward movement.

In another suitable form of the invention, the nipple for the cooling water connection extends through the tightening member acting on the contact member. This nipple comprises a sealing flange or sealing cone or the like with which it engages the outlet of the cooling water conduit in the contact member on tightening the pressure means, While the pressure required for scaling is obtained by means of a spring engaging at one end the sealing ring and at its other end the pressure means. order that the invention may be readily carried into effect, it will now be described in greater detail with reference to the accompanying drawings illustrating two embodiments of connection means for cooling agents and current and in which:

FIG. 1 is a cross-section of the contact member comprising the two ends of the inductor,

FIG. 2 is an elevational view of the device shown in FIG. 1, at the left-hand side in section, at the right-hand side in plan,

FIG. 3 shows another form of connecting means for cooling agents and current according to the invention, forthe two ends of the inductor, and

FIG. 4 is a section in plan view.

In FIGS. 1 and 2 the connecting bars to which the induction loop has to be connected are denoted by l and 1 respectively. At the ends of t ese connecting bars provision is made of contact blocks 2 and 2' respectively each provided with a cylindrical bore for receiving the inductor contact members 3, 3'. These contact morn ers have a substantially square cross-sectional area, as may be seen from FIG. 1, and merge at the back into copper tubing 4 from which the inductor is wound. In a cor responding manner the contact members have a longitudinal bore 5, 5' for the supply and exhaust respectively of the cooling agent. An insulating bridge 6 connects the two contact members mechanically.

The contact blocks 2, 2' are provided with radially inserted pressure screws '7, 7 having milled heads, which screws are arranged to act on a side face of the respective contact members. When firmly tightened they press the opposite side of the contact member firmly against the wall of the respective contact block. Since the square contact members make contact only at the edges which, as shown, are only slightly deformed, an extremely high surface pressure is exerted at these contact points, as is required for the passage of high induction currents. The sizes of the bores in the contact blocks and the contact members are such that the latter can easily be inserted Without appreciable clearance in the bores of the contact blocks with the pressure screws 7, 7 released.

For the supply and exhaust of the cooling water, the contact blocks, at the side remote from the inductor, are somewhat longer than is required exclusively for the electric contact. The bores of the contact blocks are each closed by a stop 3, 8' secured to the contact blocks in a water-tight manner. At the side, the contact block comprises nipples 9, 9' by means of which the supply and exhaust of water takes place.

Each contact member at its end remote from the in ductor has a nozzle 19 with a flexible sealing ring 11 consisting of leather, rubber or the like. This sealing ring surrounds the nozzle and engages its outer wall, an end of the member 3 having a stop, and the wall of the bore of the contact block 2. On supplying cooling water from a water means, this ring is firmly pressed against the walls against which it lies (see FIG. 2) owing to the pressure of the water, which yields an excellent seal. When inserting and removing the inductor the ring slides along the inner wall of the contact block and to be sure that, after inserting the conductor, it occupies the desired position, the stop 8 comprises a cylindrical guide ring 12 having apertures for the supply of water. This guide ring has such a size as to extend with clearance in the ring 11 and causes the latter to occupy the correct position should it have slightly shifted on insertion.

In this form of the invention the inductors can be easily and rapidly inserted and replaced, while the required contact pressure is adjustable at will by means of the milled screws 7, 7', without this pressure being transmitted to the sealing member, the ring 11. The sealing rather occurs automatically and independently of the screws '7, 7', namely by the pressure of the cooling water of the water mains. 7

In the form shown in FIGS. 3 and 4, V-shaped prisms 13, 13' are secured to the bars 1, 1 which serves as a contact block, while the ends of the copper tubing 4 used for the inductor are provided with contact members 14, 14' having an approximately semi-circular sectional area. Their semi-circular surfaces engage the faces of the prisms 13, 13' and the required high surface pressure is obtained at the contact point by means of the pressure screws 15, 15'. These pressure screws extend in guides 16, 16 secured to the bars 1, 1 and have milled heads for releasing and tightening the contact. These pressure screws act directly on the respective contact members.

For the supply of cooling agent, the pressure screws 15, 15 comprise a central bore containing an extension of the nipples 9, 9. At its inner end the extension has a sealing flange 17, 17 resting on the surface of the con-. tact member 14, 14 where the cooling conduit empties. For better sealing a leather or rubber ring may be inserted.

Tightening the sealing flange 17, 17' is effected by means of a helical pressure spring 18, 13 one end of which engages the sealing flange and the other end the pressure screw 15, 15'. This spring '18 has such a size as to exert exactly the required pressure on the sealing flange 17, 17 with the pressure screw 15, 15' firmly tightened.

To detach the connection, the pressure screw 15 is un screwed a few turns. At the same time the contact member 14 is detached and thereupon the released pressure spring 18 no longer engages the sealing flange 17 so as to allow the latter slightly to move away from the contact member 14. Then the inductor with-its two contact members can be removed directly.

In the inserted state, as shown inFIGS. 3 and 4, the surface pressure between contact member and contact block exclusively depends on the degree of tightening the pressure screw. Since invariably solid material is used, the contact pressure is adjustable to the desired value by slightly turning the pressure screw 15, 15. There is no displacement of the pressure screw in an axial direction so that the pressure acting on the sealing flange 17 is practically entirely independent of the degree of the adjusted contact pressure and depends only on the size of the pressure spring 18, 18.

What is claimed is:

1. In an inductive heating device a detachable connecting means for cooling agents and current supply comprising an inductor having an end provided with a current contact member and a cooling water supply means, a bored contact block, a pressure screw threaded through said contact block for applying pressure to said contact member to cause the latter to engage the contact block with the desired pressure, said cooling water supply means provided with a nipple and a flexible sealing ring on said contact member, a water-tight stop for the bore in said contact block and forming a chamber therebetween, said sealing ring being firmly urged by the pressure of the cooling water in said nipple chamber whereby said sealing ring is pressed against the contact member, and contact block.

2. A connecting means for cooling agents and current supply as claimed in claim 1 wherein said contact block is cylindrical-shaped while said contact member is prism- Shaped, said contact member and contact block being pressed together by said pressure screw in a direction at right angles to the longitudinal axes of said contact member and contact block.

3. In an inductive heating device a detachable connecting means for cooling agents and current supply comprising an inductor having an end provided with a current contact member and a cooling water supply means, a contact block, a pressure screw for applying pressure to said contact member to cause the latter to engage thecontact block with the desired pressure, a cooling water nipple extending through said pressure screw, a sealing flange, a helical spring pressure means acting on the sealing flange independent of the action of the pressure screw and which when tightened engages the outlet of the cooling water supply means in said contact member, said spring having one end engaging said sealing flange and the other end engaging said pressure screw.

4. In an inductive heating device a detachable connecting means for cooling agents and current supply comprising an inductor having an end provided with a current contact member and a cooling water supply means, a contact block, a pressure screw threaded through said contact block for applying pressure to said contact member to cause the latter to engage the contact block with the desired pressure, said cooling water supply means provided with a nipple, a flexible sealing ring on said contact member, said sealing ring being firmly urged by the pressure of the cooling water in said nipple whereby said sealing ring is urged against the contact member, and contact block, a cylindrical guide ring in said cooling water supply means located co-axial with said contact member and spaced from said nipple forming a Water-tight stop, said guide ring having such a proportion that when inserted together with said sealing ring in said inductive heating device said sealing ring is automatically placed in the correct position.

References Cited in the file of this patent 

1. IN AN INDUCTIVE HEATING DEVICE A DETACHABLE CONNECTING MEANS FOR COOLING AGENTS AND CURRENT SUPPLY COMPRISING AN INDUCTOR HAVING AN END PROVIDED WITH A CURRENT CONTACT MEMBER AND A COOLING WATER SUPPLY MEANS, A BORED CONTACT BLOCK, A PRESSURE SCREW THREADED THROUGH SAID CONTACT BLOCK FOR APPLYING PRESSURE TO SAID CONTACT MEMBER TO CAUSE THE LATTER TO ENGAGE THE CONTACT BLOCK WITH THE DESIRED PRESSURE, SAID COOLING WATER SUPPLY MEANS PROVIDED WITH A NIPPLE AND A FLEXIBLE SEALING RING ON SAID CONTACT MEMBER, A WATER-TIGHT STOP FOR THE BORE IN SAID CONTACT BLOCK AND FORMING A CHAMBER THEREBETWEEN, SAID 